/**
 * Alipay.com Inc.
 * Copyright (c) 2004-2012 All Rights Reserved.
 */
package com.alipay.api;

import java.io.IOException;
import java.io.InputStream;
import java.io.InputStreamReader;
import java.io.OutputStream;
import java.io.Reader;
import java.io.StringWriter;
import java.io.Writer;

/**
 * 
 * @author runzhi
 */
public class StreamUtil {
  private static final int DEFAULT_BUFFER_SIZE = 8192;

  public static void io(InputStream in, OutputStream out) throws IOException {
    io(in, out, -1);
  }

  public static void io(InputStream in, OutputStream out, int bufferSize) throws IOException {
    if (bufferSize == -1) {
      bufferSize = DEFAULT_BUFFER_SIZE;
    }

    byte[] buffer = new byte[bufferSize];
    int amount;

    while ((amount = in.read(buffer)) >= 0) {
      out.write(buffer, 0, amount);
    }
  }

  public static void io(Reader in, Writer out) throws IOException {
    io(in, out, -1);
  }

  public static void io(Reader in, Writer out, int bufferSize) throws IOException {
    if (bufferSize == -1) {
      bufferSize = DEFAULT_BUFFER_SIZE >> 1;
    }

    char[] buffer = new char[bufferSize];
    int amount;

    while ((amount = in.read(buffer)) >= 0) {
      out.write(buffer, 0, amount);
    }
  }

  public static OutputStream synchronizedOutputStream(OutputStream out) {
    return new SynchronizedOutputStream(out);
  }

  public static OutputStream synchronizedOutputStream(OutputStream out, Object lock) {
    return new SynchronizedOutputStream(out, lock);
  }

  public static String readText(InputStream in) throws IOException {
    return readText(in, null, -1);
  }

  public static String readText(InputStream in, String encoding) throws IOException {
    return readText(in, encoding, -1);
  }

  public static String readText(InputStream in, String encoding, int bufferSize) throws IOException {
    Reader reader = (encoding == null) ? new InputStreamReader(in) : new InputStreamReader(in, encoding);

    return readText(reader, bufferSize);
  }

  public static String readText(Reader reader) throws IOException {
    return readText(reader, -1);
  }

  public static String readText(Reader reader, int bufferSize) throws IOException {
    StringWriter writer = new StringWriter();

    io(reader, writer, bufferSize);
    return writer.toString();
  }

  private static class SynchronizedOutputStream extends OutputStream {
    private OutputStream out;
    private Object       lock;

    SynchronizedOutputStream(OutputStream out) {
      this(out, out);
    }

    SynchronizedOutputStream(OutputStream out, Object lock) {
      this.out = out;
      this.lock = lock;
    }

    public void write(int datum) throws IOException {
      synchronized (lock) {
        out.write(datum);
      }
    }

    public void write(byte[] data) throws IOException {
      synchronized (lock) {
        out.write(data);
      }
    }

    public void write(byte[] data, int offset, int length) throws IOException {
      synchronized (lock) {
        out.write(data, offset, length);
      }
    }

    public void flush() throws IOException {
      synchronized (lock) {
        out.flush();
      }
    }

    public void close() throws IOException {
      synchronized (lock) {
        out.close();
      }
    }
  }
}
